def no_teen_sum(a, b, c):
  if a in [13,14,17,18,19]:
    if b in [13,14,17,18,19]:
      if c in [13,14,17,18,19]:
        return 0
      else:
        return c
    if c in [13,14,17,18,19]:
      return b
    else:
      return b+c
      
  if b in [13,14,17,18,19]:
    if c in [13,14,17,18,19]:
     return a
    else:
     return a+c
    
  if c in [13,14,17,18,19]:
    return a+b
  
  else:
    return a+b+c
  
